title: Progressive kyphosis after vertebroplasty in osteoporotic vertebral compression fracture.
abstract: METHODS
  A single-center retrospective study.
  
  
  OBJECTIVE
  To identify the relevant incidence and risk factors of delayed vertebral collapse and progressive kyphosis with spinal canal encroachment after percutaneous vertebroplasty (PVP) for vertebral compression fracture (VCF).
  
  
  BACKGROUND
  Delayed vertebral collapse and progressive kyphosis with spinal canal encroachment are complications after PVP for VCF.
  
  
  METHODS
  Between December 2002 and February 2011, 843 patients underwent PVP for VCFs for at least 2 years of minimum follow-up term in a tertiary referral center. All imaging measurements were obtained digitally, with comparisons of the Cobb angle and spinal canal stenosis on fractured vertebral level at 3 different time points of pre- and postvertebroplasty, and before revision surgery.
  
  
  RESULTS
  Thirteen patients (14 fractures) who underwent PVP had delayed vertebral collapse and progressive kyphosis on the level of the fractured vertebra, 3 were male and 10 female, with a median age of 75 years (range, 66-89 yr). One had 2-level VCFs. All were treated with revision surgery of decompressive laminectomy for spinal canal stenosis with neurological complications. Twelve patients had additional instrument fixation. The involved vertebras were concentrated at the thoracolumbar junction region (T11-L2). The mean Cobb angles were measured at 23.67° before PVP, 15.90° after PVP, and 30.92° before revision surgery. The ratio of spinal canal stenosis was 35.45% and 49.48% before PVP and revision surgery, respectively. The occurrence rate of delayed complications was about 1.5% (13/843).
  
  
  CONCLUSIONS
  Conservative treatment and minimal invasive vertebral augmentation surgery can be selected from patients with stable VCFs. Close follow-up is warrant to monitor the occurrence of late collapse with neurological complications.
  
  
  METHODS
  N/A.
authors.affiliation: *Department of Neurological Surgery †Department of Radiology, Tri-Service General Hospital, National Defense Medical Center and ‡Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Kuan-Nien
authors.initials: KN
authors.lastname: Chou
authors.forename: Bon-Jour
authors.initials: BJ
authors.lastname: Lin
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Wu
authors.forename: Ming-Yin
authors.initials: MY
authors.lastname: Liu
authors.forename: Dueng-Yuan
authors.initials: DY
authors.lastname: Hueng
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D050815:Fractures, Compression / Q000601:surgery*; D006801:Humans; D007738:Kyphosis / Q000209:etiology* / Q000601:surgery; D007796:Laminectomy; D008159:Lumbar Vertebrae / Q000293:injuries / Q000601:surgery; D008297:Male; D058866:Osteoporotic Fractures / Q000601:surgery*; D012086:Reoperation; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000601:surgery*; D013904:Thoracic Vertebrae / Q000293:injuries / Q000601:surgery; D016896:Treatment Outcome; D054854:Vertebroplasty / Q000009:adverse effects*